In an image forming apparatus, such as an MFP (a Multi-Function Peripheral), an image is formed on a sheet recording medium such as paper or the like (hereinafter will be referred to as “paper”). In order to erase the image formed on the paper and reuse the paper, the image is printed on the paper using an erasable coloring material such as ink containing a leuco dye. The erasable coloring material is erased by applying heat thereto at a high temperature.
The color erasing apparatus is configured to have a heat roller, into which a roller type heat source is built-in similar to a fuser (fixing) unit, and a press roller with an interposing paper transporting path. The heat roller and the press roller are arranged to face each other. The color erasing apparatus transports the printed paper by rotating the heat roller (the heat source) along with the press roller with the paper pinched therebetween. The image that had been formed on the paper is erased by heating the printed paper as it rolls moves between the press roller and a heat roller.
However, the printed paper being transported to the heat source (the color erasing unit) of the color erasing apparatus has been used at least once. Unlike new paper, the printed (used) paper may be guided to the color erasing unit in a deformed state, such as being wrinkled, folded, having a hole therein, or the like. The color erasing is achieved by heating the toner on the surface of the transported paper. The surface of the used paper is rapidly heated as it passes through the color erasing unit, vaporizing the moisture in the paper, and causing a subtle change in the size of the paper. Further wrinkling of the paper may occur when the used paper is heated and pressed by the rollers while passing through the color erasing unit. Therefore, transporting the paper becomes extremely unstable and paper jamming may occur.
The probability of a paper jam increases for used paper transported while applying roller pressure and heat. When a paper jam occurs at the color erasing unit, the paper is freed by releasing the pressure from the press roller or by turning a knob connected to the press roller for rotating it to release the jammed paper therefrom.